Rusty Iron Keel After Priming and 2 Coats of Anitfouling

[carboman]

Maybe its not as bad as I think, but i ground the keel down to as clean a metal surface as i could. It was black not shiny because i think the PO used Fozz or a metal sealer of some sort.

So afetr grinding i used interlux primocon, 4 coats at least, then have applied 3-4 coats of Interlux micron extra w/biolux, black.

Seems like after it rains, it starts to rust. The water is running off the boat and down the keel. Not concerned on that, but more concerned about it lasting in the water. Any ideas?

 

[navigator97]

I have an Iron Keel on my H-33.5 When there have been rust sopts showing after haulout, I would wire brush and sand down, Then apply 2 coats of Pettit Rust-lok to it. hat seals in and prevents further rusting. I then put on 2 coats of anti-fouling paint (in my case I used Pettit Trinadad SR. There have been fewer and fewer rust spots showing each year. It probably would have been better to have sanded down the whole keel some years back and then have done the whole keel in Pettit Rust-Lok.

 

[whatfiero]

rusty keel

your never gonna get all of it unless you sandblast and seal the whole thing just keep grinding feathering epoxy paint till no more rust wait till ya hang in sling to do the bottom 6 coats of paint and then bottom paint takes longer than 1 night see if they can hang ya on a sunday

 

[marginal]

Did you sanded the keel down to clean metal ? If not, the paint left on the keel had probably some rust under it and this is what makes rust spots reappear.

regards !

 

[sesmith]

It may help to treat the areas with phosphoric acid (aka, naval jelly) prior to painting.

 

[Crazy Dave Condon]

If you ever take paint off an iron keel, I would suggest all and restart over. In my dealership we use to:

1. Sandblast but mask off the hull where connected to keel with tape or wire brushed using a drill or something along that line. Whatever you do, wear protection for eyes, ears, nose and clothing. Make sure it is away from other boats as the dust flies and will get into pores and then you have a mess on your hands.
2. Apply zinc chromate to protect the metal from corrosiion.
3. Fill in holes with a two part epoxy the kind designed specifically for underwater use
to smooth out the surface of the keel.
4. Apply minimum 4 coats of epoxy barrier better with 6
Lightly sand between coats.
5. let dry for a couple of days and then sand the surface of the epoxy barrier coat for
adhesion of any bottom paint.

I realize this is alot of workl but rarely did I ever see any boat return with rust spots as I warrantied my work for two years.

crazy dave condon

 

[carboman]

Did you ever use a pressure washer with a sandblaster attachment? What about the type and brand of zinc chromate paint?

Thanks!

 

[Crazy Dave Condon]

Carboman;

I have that equipment but never tried it. It could work but suggest that you still cover the hulll so you will not damage the fiberglass.

In my heyday, it was call Zinc Chromate on the can but now called differnt names but essentially it is a metal primer and just look on the can to see if it says zinc chromate and you will be fine. Not sure about other style metal primers but that worked very well with me but the key is getting a clean surface.

Anyone has a good suggestion would be helpful please.

crazy dave condon

 

[seadaddler]

Pettit

Pettit trinadad makes a special primer for iron keels,I was told my keel on my 2007 H-36 but I am thinking it is not Iron because never have seen any rust at all.
Next time I dive I need to bring a magnet to check for sure.
Nick

 

[Richard Bryer]

Re: Pettit

According to this site, it is lead: http://hunter.sailboatowners.com/index.php?option=boats&task=displaymodel&id=71&Itemid=888&brand=Hunter&bmodel=36

 

[anchorclanker]

A pressure washer sandblaster is mind blowing. I went after a 50 year old 500 gallon propane tank that had rust bubbles in the paint and lots and lots of pits. 15 minutes and 2 bags of sand and it was 100% totally clean bare metal.

A friend borrowed it to blast his swimming pool, and had to stop. It abraded almost 2 inches of the surface in the first few seconds.

 

[Crazy Dave Condon]

Seadaddler;

Orginally the 36 came with a lead keel either wing or deep fin keel depending on choice of keels. It has since changed due to increased costs of lead.

crazu dave condon

 

[carboman]

Can anyone remember what brand of zinc chromate they used for their iron keels? I see some at west marine, but it says its for aluminum above or below the water line, not iron.

Thanks!